Plastic encased metal ribbed flexible conveyor chain

ABSTRACT

An improved flexible conveyor chain with side flexing capability while retaining good cross-sectional areas at stress positions. The chain structure is made of metal rib sections encased in plastic material which provides positive positioning and even cooling effects during manufacturing and strength in useage. The plastic material reduces or eliminates the need for chain lubrication. The edges of the chain elements have ramp edges to assist in ease of loading and unloading material to be moved by the conveyor chain.

United States Patent Kampfer 1 Mar. 7, 1972 [54] PLASTIC ENCASED METALRIBBED FLEXIBLE CONVEYOR CHAIN [72] Inventor: David H. Kampier, St.Paul, Minn.

[73] Assignee: Conveyor Specialties Company, St. Paul,

Minn.

[22] Filed: Sept. 28, 1970 21 Appl. No.: 75,998

[52] US. Cl. ..59/78, 59/84, 74/250 C, 198/ 189 [51] Int. Cl. ..Fl6g15/12 [58] Field of Search ..59/78, 80, 82, 90, 84; 198/189; 74/246, 250R, 250 C, 251 R, 251 C [56] References Cited FOREIGN PATENTS ORAPPLICATIONS 697,288 1 1/1964 Canada ..59/79 France 198/ l 89 France198/ 1 89 Primary ExaminerCharles W. Lanham Assistant Examiner-Gene P.Crosby Attorney-Frank B. Hill [57] ABSTRACT 4 Claims, 5 Drawing FiguresPATENTEDHAR 7 I972 SHEET 1 OF 2 fer IN VENTOR. flay/0 A! Kan BY ATTORNEYPATENTEDMAR 7 I972 sum 2 [IF 2 IN VEN TOR. flay/o A4 Kamp/er ATTORNEYPLASTIC ENCASED METAL RIBBED FLEXIBLE CONVEYOR CHAIN This inventionrelates generally to a metal ribbed, plastic encased, side flexibleconveyor chain assembly and more par ticularly to a metal ribbedconveyor chain assembly having uniquely shaped outer chain assembliesand center bar assemblies which have knurled end pins which facilitateease of assembly while providing positive and accurate locating means.

Continual improvement and advancement is being made in variousmanufacturing and assembly facilities in a direction of automatingproduction activities. One of the major thrusts is in eliminating laborwhich is doing manual type of activities that can be accomplished aswell or better by programmed and automated systems.

This type of automation advancement is being completed in the packagingfield for both food and nonfood items. Many industries, such as thediary industry, are moving to larger and more centralized dairy productpackaging plants. These centralized plants require longer conveyor linesand more flexability in the direction of the conveyor lines. There is aneed to reduce maintenance to a minimum while providingas muchflexability in the systems as possible-Because the conveyor acts on fooditems, it is desirable if lubricants can be reduced or eliminated,helping to eliminate the'unsightly appearance and the maintenancerequirements. Some of the conveyor lines extend over long distances andin order to conserve floor space and provide the flexability, curvedpaths are required.

As the length of the'line increases, strength is important to be presentin the chain assembly. Reductions in weight of the chain withoutelimination of needed strength is a desirable feature. One of theprincipal objections of the present invention is to provide a flexibleconveyor chain which gives a good range of side flexing capacity andprovides necessary strength at the needed areas.

Another object of the present invention is to provide a side flexingconveyor chain assembly which can move over extended lengths of distanceand where lubrication characteristics will be inherent in the materialand will not be required externally on the chain.

A still further object of the present invention is to provide a conveyorchain, having side flexability features while providing ramped edges toassist in loading and unloading items to be transferred, eliminating orreducing to a minimum 'hangups of the products being transferred anddamage to the conveyor system.

A still further object of the present invention is to provide a flexibleconveyor chain having the features of the present invention, including asteel center bar encased in plastic, which assists in manufacturing byproviding cooling characteristics when the elements are being formed soeven cooling will take place in the plastic while at the same timeproviding additional strength and positive locating of the necessaryelements during assembly and use.

Also, an object of the present invention includes the provision of aside flexible encased steel center bar chain capable of accomplishingthe above specified objectives-with a minimum of material and equipmentcosts and manufacturing expense; and at the same time being composed ofsimple, interchangeable and ruggedly formed structures which will beextremely flexible and useful in application.

To the accomplishment of the foregoing and related ends, the inventionthen consists of the means and features hereinafter fully described andparticularly pointed out in the claims. The annexed drawings and thefollowing description setting forth, in detail, certain means forcarrying out this invention. Such disclosed means illustrating, however,one of various ways in which the principles of the invention may beused.

In the annexed drawings:

FIG. 1, is a top plan view of a side flexible conveyor chain assemblyand illustrating the principles of the present invention.

FIG. 2, is a partial cross-sectional top plan view of a side flexibleconveyor chain assembly as illustrated in FIG. I, flexing in a leftdirection when viewed from the left of the drawing to the right of thedrawing.

FIG. 3 is a top plan view of a side flexible conveyor chain assembly asillustrated in FIG. I, flexing in a right direction when viewed from theleft of the drawing to the right of the drawing.

FIG. 4, is a partial cross-sectional view taken along the pin member,showing the structure of the side flexible conveyor chain assembly,taken generally along line 4-4 of FIG. 1.

FIG. 5, is a partial side elevated view of a side flexible conveyorchain assembly showing the center bar assembly and its relationship tothe side bar member, taken generally along line 5'5 of FIG. 1.

A general description of this invention is a side flexible conveyorchain assembly having chain elements made up of two interchangeable sidebar members forming an outer chain assembly and a center bar assemblywhich connects adjacent outer chain assemblies which are made up of twoside bar members by knurled end locating or surface pins. The side barmembers are so constructed as to provide the largest crosssectional areawhere the locating pins are acting. Thus maintaining good strength atthe work area. The pins are provided with knurled ends which can actboth on the metal rib members positioned in the side bar members and theplastic encasing material, to provide positive positioning of thelocating pins and'easy assembly of the conveyor chain assembly. Thelocating pins are provided with locating shoulders which act onmetalsurfaces to provide proper spacing between the side bar members.Tapered surfaces are provided on the side bar members and on the end ofthe center bar assembly to permit flexing of the conveyor chain aroundcurved paths and providingspace for the chain to flex during the curvedportion of its travel.

Referring generally to the figures, there is illustrated a flexibleconveyor chain generally referred to by numeral 10. The flexibleconveyor chain assembly 10 is made up of a series of outer chainassembly members and center bar assembly members that are connectedtogether to form an endless chain. This basic concept is a practice wellknown in the art. The specific elements forming the present flexibleconveyor chain 10 are referred to as outer chain assembly 11 and centerbar assembly 12. The function and structure of these individual elementswill be explained in detail below.

The outer'bar assembly 11 is provided with two side bar members l4.whichare connected together by two pin members 15. The side bar members 14have the same structural form and are positioned opposite of each otheron the ends of the pin members 15 as shown in FIG. 1; for example, andwill be explained in more detail below. The side bar member 14 has anouter surface 17, a circumferential surface 18 and an inside surface 19.The outer surface 17 is connected to the circumferential surface 18 by aramp edge 21. The inside surface 19 has a central portion 23, an outertapered surface 24 and an inner tapered surface 25, at each end. Thecentral portion 23 and outer' tapered surface 24 act together to form aload section 26 to act with the pin members 15 as will be explainedbelow in detail.

The outer bar member 14 has a metal rib 27 which is substantiallypositioned in its central portion. The metalrib 27 is provided withlocating or pin surfaces 28. The metal rib 27 also provides for passageholes 29. The side bar members 14 are provided with pin holes 31 whichare made up of pin body hole 32 and knurl hole 34, both of which aresubstantially aligned with the locating or pin surface 28. A shouldersurface 36 is provided on the metal rib 27 as best viewed in FIGS. 2 and4.

The side bars members 14 of the outer chain assembly 11 are heldtogether in spaced relationship by pin members 15. The pin member 15 hasa pin body surface 41 with a predetermined diameter dimension with twoknurled ends 42 which have an outer diameter less than the diameter ofpin body surface 41 and have a shoulder 43 which connects them. When theouter chain assembly 11 is assembled, the pin body surface 41 will bepositioned in the pin body hole 32. The distance between the twoside barmembers 14 will be predetermined by the shoulder 43 acting on theshoulder surface 36. The pin member 15 will be firmly secured inassembled position by the knurling end 42 acting with the knurl hole 34and the locating or pin surface 28 of the metal rib 27. The shouldersurface 36 gives a positive surface for the shoulder 43 to be locatedoff of, providing a predetermined centered spacing of the side barmembers 14 and their various elements.

The center bar assembly 12 is provided with a metal rib 46 which has endopenings 47 and passage holes 48. The end opening 47 has a locatingsurface 49, the function of which will be discussed in more detailbelow. The center bar assembly 12 has an outer surface 51 which extendsaround and is the circumference of the center bar assembly 12. Thecenter bar assembly 12 has side surfaces 52. At the upper and bottomportions of the center bar assembly 12 as best viewed in FIG. 4, rampedges 53 connect the side surface 52 and the outer surface 51. Taperedends 55 are provided on both ends of the center bar assembly 12.Elongated pin holes 57 are provided in the center bar assembly 12 topermit the pin members 15 to pass through the center bar assembly andact with the body surface 41 of the pin 15.. When the flexible conveyorchain is finally assembled, the pin member will be passed through theelongated pin holes 57 before the side bar members 14 are held in placeby the knurl ends 42 as discussed above.

It should be noted that the widest cross section of the side bar member14 is the load section 26 which is well positioned substantially at theaxis of the pin member 15, giving the biggest bulk of strength where theload is carried. At the same time, the largest width of the center barassembly 12 is where the elongated pin holes 57 act with the pin member15. The chain structure permits substantial flexability of the conveyorchain 10 by providing the outer tapered surface 24 and the inner taperedsurface 25 on the side bar members 14 and the tapered ends 55 at theends of the center bar assembly 12. When the flexible conveyor chain 10is moved in the direction of the arrow indicated by the letter M, thecenter bar assembly 12 will have its trailing elongated pin hole 57pulling on the pin member 15 its associated with. The leading elongatedpin hole 57 will be moved forward by having the pin member 15 acting onthe leading edge of its elongated pin hole 57. The tapered surfaces 24and 25, and ends 55, permit the conveyor chain 10 to flex during itstravel on curved paths while at the same time permitting maximum crosssections to receive full thrust of the load on the conveyor chain. FIG.2, generally illustrates a left turn and FIG. 3, generally illustrates aright turn, when the conveyor chain 10 is traveling in the M direction.

During manufacturing, the locating or pin surfaces 28 act as positivelocating surfaces to have the outer plastic shell of the side bar memberform around the metal rib 27. The metal rib 27 also provides passageholes 29 which assist in securing the outer plastic shell and the metalrib 27 together in a strong bond structure. Because of the large widthprovided at the load section 26, and the length of the side bar member14, good cooling characteristics are necessary to provide a goodfinished part. If good cooling characteristics are not provided, warpageand distortion will occur in the part. The metal rib provides coolingcharacteristics for the encasing material which can be cast out ofplastic material such as Delrin, for example. The locating pin surface28 gives a positive positioning in the casting where the parts arefonned and also for the side bar member 14 when the outer chain assembly11 is formed by providing a metal shoulder surface 36 to act with theshoulder 43 ofthe pin member 15.

The center bar assembly 12 is provided with the metal rib 46 which actsin a similar manner to the side rib 47 to provide coolingcharacteristics in the casting operation when the part is produced. Theouter shell of the encasing material can be made of plastic, such as,Delrin. The end openings 47, as best viewed in FIG. 5, are larger thanthe elongated pin hole 57 and provide an exposed locating surface 49 atone portion of pin hole 27 which is used during forming of the centerbar assembly and to positively locate the thickness of the outer shellor encasing material between the side surfaces 52 and the metal rib 46.The passage holes 48 permit good distribution of the plastic materialand good securing of the metal rib 46 in the central bar assembly 12.The ramp edges 21 and 53 provided on the side bar members 14 and on thecenter bar assembly l2, permit easy passage onto and off of the conveyorchain 10 for products which this conveyor chain will move from onelocation to another. This type of conveyor chain 10 can be used in areasof extended distances where water may be prevalent for the plantsoperation and where sharp or substantially sharp travel curves arenecessary. The plastic characteristics of the encasing materials aresuch that lubrication is not required. Thus, eliminating the need forlubricating the conveyor chain. This is important particularly wherewater is prevalent. It eliminates the necessity of putting the lubricanton the chain members which in turn will pass onto the items beingcarried; and also, eliminates the cost of this type of maintenanceservice. The deterioration of the conveyor chain due to rusting is alsoeliminated, and the chain surface does not scratch, damage, et cetera,merchandise carried on it.

While but one form of the structure of the invention has been shown anddescribed, other forms within the spirit and scope of the structure ofthis invention will now be apparent to those skilled in the art.Therefore, the embodiment shown in the drawings is to be considered asmerely set forth for illustrative purposes, and is not intended to limitthe scope of the invention herein described and shown.

Other modes of applying the principles of my invention may be employedinstead of those explained, change being made as regards the meansherein disclosed, provided those stated by any of the following claimsor their equivalent be employed.

1 therefore particularly point out and distinctly claim as my invention:

1. A plastic encased metal ribbed flexible conveyor chain comprising, incombination:

a. at least one outer chain assembly;

b. said outer chain assembly having two side bar members;

c. a pin hole near each end of said side bar member;

d. a metal rib running the length of said side bar member;

e. a pair'of pin members;

f. securing means to position said pin members in said pin holes toalign said side bar members;

g. at least two center bar assemblies;

h. an elongated hole in each end of said center bar assembly;

i. a metal rib running the length of said center bar assembly;

j. said center bar assemblies having tapered ends;

k. said side bar members having an outer surface and an in side surface;

I. said side bar members having load sections substantially at said pinholes;

in. an outer tapered surface as part of said inside surface andextending from the pin hole to the end of said side bar member in thedirection of the outside surface; and

n. an inner tapered surface as part of said inside surface and extendingfrom the pin hole to the middle of said side bar member in the directionof the outside surface.

2. A conveyor chain as claimed in claim 1, including:

a. a circumferential surface around the outside of said side barmembers; and

b. a first ramp edge connecting said outer surface and saidcircumferential surface.

3. A conveyor chain as claimed in claim 2, including:

a. an outer surface extending around said center bar assembly;

b. side surfaces as part of said center bar assembly; and

c. a second ramp edge connecting said outer surface and said sidesurfaces of said center bar assembly.

4. A conveyor chain as claimed in claim 1, including:

a. said pin holes include a knurl hole and a pin body hole;

b. said pin member includes two knurl ends and a body sursecuring means;

face; f. said body surface acting in said pin body hole; and

Fhoulders Connecllng said knul'l ends and Said body g. said shoulderacting on said shoulder surface to assist in ace;

d. a shoulder surface connecting said pin body hole and said 5 :L i SaldSide bar members a predetermined Space knurl hole;

c. said knurl end acting in said knurl hole as part of said

1. A plastic encased metal ribbed flexible conveyor chain comprising, incombination: a. at least one outer chain assembly; b. said outer chainassembly having two side bar members; c. a pin hole near each end ofsaid side bar member; d. a metal rib running the length of said Side barmember; e. a pair of pin members; f. securing means to position said pinmembers in said pin holes to align said side bar members; g. at leasttwo center bar assemblies; h. an elongated hole in each end of saidcenter bar assembly; i. a metal rib running the length of said centerbar assembly; j. said center bar assemblies having tapered ends; k. saidside bar members having an outer surface and an inside surface; l. saidside bar members having load sections substantially at said pin holes;m. an outer tapered surface as part of said inside surface and extendingfrom the pin hole to the end of said side bar member in the direction ofthe outside surface; and n. an inner tapered surface as part of saidinside surface and extending from the pin hole to the middle of saidside bar member in the direction of the outside surface.
 2. A conveyorchain as claimed in claim 1, including: a. a circumferential surfacearound the outside of said side bar members; and b. a first ramp edgeconnecting said outer surface and said circumferential surface.
 3. Aconveyor chain as claimed in claim 2, including: a. an outer surfaceextending around said center bar assembly; b. side surfaces as part ofsaid center bar assembly; and c. a second ramp edge connecting saidouter surface and said side surfaces of said center bar assembly.
 4. Aconveyor chain as claimed in claim 1, including: a. said pin holesinclude a knurl hole and a pin body hole; b. said pin member includestwo knurl ends and a body surface; c. shoulders connecting said knurlends and said body surface; d. a shoulder surface connecting said pinbody hole and said knurl hole; e. said knurl end acting in said knurlhole as part of said securing means; f. said body surface acting in saidpin body hole; and g. said shoulder acting on said shoulder surface toassist in placing said side bar members a predetermined space apart.